Search for $K^+\to\pi^+\nu\bar{\nu}$ at NA62

Abstract

The decay $K^+\to\pi^+\nu\bar{\nu}$ is highly suppressed in the Standard Model (SM), while its rate can be predicted with minimal theoretical uncertainty. The branching ratio (BR) for this decay is thus a sensitive probe of the flavor sector of the SM; its measurement, however, is a significant experimental challenge. The primary goal of the NA62 experiment is to measure ${\rm BR}(K^+\to\pi^+\nu\bar{\nu})$ with 10% precision. NA62 took data in pilot runs in 2014 and 2015, reaching the design beam intensity. The status of the experiment and the prospects for the measurement of ${\rm BR}(K^+\to\pi^+\nu\bar{\nu})$ are presented.